Sam,
I just so happens that we discussed CME a few days ago in this thread...
http://www.network54.com/Forum/thread?forumid=251727&messageid=1109653325&lp=1109797238
CME is not my favorite way to play a primary bull market in commodities, not only for the reasons I noted in the thread, but because CME has grown to be primarily a financial instrument futures exchange. So today they trade a lot more S&P, cuurency, and debt instrument futures than they do cattle, hogs, and pork bellies.
As noted in the thread and on the web site, I much prefer BHP over CME as a commodity proxy. That's not to say that CME is not a good buy. It may be. I just wouldn't buy it as a commodity play.
Larry